BS EN ISO 2719:2002 pdf download – Determination of flash point — Pensky-Martens closed cup method
9 Sample handling
9.1 Petroleum products
9.1.1 Subsampling Subsample at a temperature at least below the expected flash point. If an aliquot of the original sample is to be stored prior to testing, ensure that the container is filled to more than of its capacity (see note to 1 0.1 ).
9.1.2 Samples containing undissolved water If a sample contains undissolved water, decant an aliquot from the water prior to mixing. Flash point results can be affected by the presence of water. For certain fuel oils and lubricants, it may not always be possible to decant the sample from the free water. In such cases, the water should be separated from the aliquot physically, prior to mixing, or, if this is not possible, the material should be tested in accordance with ISO 3679  .
9.1.3 Samples that are liquid at ambient temperature Mix samples by gentle manual shaking prior to the removal of the test portion, taking care to minimize the loss of volatile components, and proceed in accordance with clause 1 0.
9.1.4 Samples that are semi-solid or solid at ambient temperature Heat the sample in its container in a heating bath or oven (6.4) to a temperature of , or a higher temperature not exceeding below the expected flash point, whichever is the greater, for . If after the sample is still not completely liquefied, extend the preheating for further periods as required. Avoid overheating the sample, as this could lead to the loss of volatile components. After gentle agitation, proceed in accordance with clause 1 0.
9.2 Paints and varnishes Prepare the samples in accordance with ISO 1 51 3.
10.1 General NOTE Results of flash point determinations may be affected if the sample volume falls below of the container capacity. Care should be taken when testing samples of residual fuel oil which contain significant amounts of water, as heating these samples may cause them to foam and eject from the test cup.
10.2 Procedure A
10.2.1 Using a barometer (6.3), record the ambient barometric pressure in the vicinity of the apparatus at the time of test. NOTE It is not necessary to correct the barometric pressure to , although some barometers are designed to make this correction automatically.
10.2.2 Fill the test cup (see 7.3) with the test portion to the level indicated by the filling mark. Place the lid on the test cup and put it in the heating chamber. Ensure that the locating or locking device is properly engaged and insert the thermometer (6.2). Light the test flame and adjust to a diameter of to , or switch on the alternative ignition source. Light the heater flame or switch on the electric heater and supply heat at such a rate that the temperature of the test portion as indicated by the thermometer increases at to , and maintain this heating rate throughout the test. Stir the test portion at a rate of to , stirring in a downward direction.
10.2.3 When the test portion is expected to have a flash point of or below, make the first application of the ignition source when the temperature of the test portion is below the expected flash point, and thereafter at temperature intervals. Cease stirring and apply the ignition source by operating the mechanism on the cover, which controls the shutter and ignition source, so that the source is lowered into the vapour space of the test cup in , left in its lowered position for , and quickly raised to its high position.
10.2.4 When the test portion is expected to have a flash point of above , make the first application of the ignition source when the temperature of the test portion is below the expected flash point, and thereafter at temperatures which are a multiple of . Cease stirring and apply the ignition source by operating the mechanism on the cover, which controls the shutter and ignition source, so that the source is lowered into the vapour space of the test cup in , left in its lowered position for , and quickly raised to its high position.
10.2.5 When testing a material of unknown flash point, conduct a preliminary test at a suitable starting temperature. Make the first ignition-source application at above the starting temperature and follow the procedure given in 1 0.2.3 or 1 0.2.4, as applicable. 10.2.6 Record, as the observed flash point, the temperature of the test portion read on the thermometer at the time when the ignition-source application causes a distinct flash in the interior of the test cup. Do not confuse the true flash point with the bluish halo that sometimes surrounds the ignition source at applications preceding the actual flash point.